Understanding Exactly Why People Cheat

30-40% of Americans Cheat

More than 90% of Americans believe infidelity is unacceptable, yet 30-40% of people cheat. Infidelity is associated with adverse outcomes such as depression, domestic violence, divorce, even homicide. Considering these negative effects, why do people cheat? And is the phrase “once a cheater, always a cheater” true?

Let’s start to answer by considering three primary types of reasons for cheating:

1. Individual reasons. The phrase “once a cheater, always a cheater” refers to individual reasonsfor cheating—qualities about the person that make him or her more prone to commit infidelity. Researchers have identified a variety of individual risk factors, including:

Gender. Men are more likely than women to cheat, largely because men have more testosterone, which is responsible for the strong desire to have sex.

Personality. Those who have less conscientious and less agreeable personalities are more likely than people high on these traits to cheat. (If you’re wondering about your own personality, try this assessment.

Religiosity and Political Orientation. Very religious people and those with a conservative political orientation are less likely than others to cheat because they have more rigid values.

2. Relationship reasons. People also cheat because of relationship reasons—characteristics about their relationship itself that are unsatisfying. For these people, becoming involved in a well-matched partnership diminishes or eliminates their desire to cheat. “Once a cheater, always a cheater” does not hold true for this group. When they stray, factors about the relationship itself must be examined. Researchers find that partnerships characterized by dissatisfaction, unfulfilling sex, and high conflict are at higher risk for infidelity. Also, the more dissimilar partners are—in terms of personality, education level, and other factors—the more likely they are to experience infidelity.

3. Situational reasons. Others cheat because of the situation: A person might not have a personality prone to cheating, and might be in a perfectly happy relationship, but something about their environment puts them at risk of infidelity. Some situations are more tempting than others. Spending time in settings with many attractive people can make cheating more likely. The nature of a person’s employment is also related to infidelity—individuals whose work involves touching other people, having personal discussions, or a great deal of one-on-one time are more likely to cheat. When the sex ratio is imbalanced (an overabundance of men or women in the work or campus environment), people are also more likely to experience infidelity. Finally, people who live in urban areas, as opposed to rural, less populated regions, are at greater risk—people in metropolitan locations generally have more liberal attitudes about extramarital sex, and cities simply have more people, creating an environment of higher anonymity and a larger potential group of partners with whom to have sex.

How can you protect your relationship from infidelity?

First, talk to your partner about their definition of infidelity. People have different ideas about what constitutes cheating and partners need to develop consensus. It is easier to understand where the boundaries are and what will hurt your partner if you have had an open discussion about it. Most people agree that sex with another person constitutes infidelity but the reaction to other behaviors can be more nuanced. Does going out for lunch with an attractive coworker constitute infidelity? What about sexy chat sessions with strangers online? Open discussions about such questions will help set boundaries and hopefully avoid hurt feelings down the line.

If you are a person who struggles with infidelity, as a victim or participant, it is important to get help, through therapy or books by professionals with advanced degrees in psychology. “Once a cheater, always a cheater” does not have to ring true for you.